Book Summary: Why Zebras Don’t Get Ulcers by Robert Sapolsky

Imagine a zebra on the African savannah, peacefully munching grass. Suddenly, a lion appears. Instantly, the zebra’s body goes into overdrive: adrenaline surges, the heart races, blood pumps to the muscles. It’s all hands on deck for a fast escape. But once it’s safe, the zebra returns to normal, the threat forgotten. No lingering worries about future lion attacks.

Now, picture us humans. We don’t need lions to trigger our stress response. Bills, work deadlines, relationship problems—these all act as “lions” in our heads, keeping us stressed for days, weeks, even years. Prof. Sapolsky’s key point? Unlike zebras, we stress about everything, all the time. And our bodies just aren’t built for that kind of chronic stress.

Here’s where things get interesting. Our bodies respond to stress in incredible ways, releasing hormones like adrenaline and cortisol that are designed to handle short-term crises. These chemicals make us faster, sharper, more powerful in the moment. But when they stay elevated for too long, they start to wreak havoc, affecting nearly every system we have.

How Chronic Stress Messes with Our Health

• Heart and Blood Pressure: Constantly elevated blood pressure from stress doesn’t just go away. Over time, it damages arteries and raises the risk of heart disease.
• Digestion Woes: Our bodies aren’t interested in digesting lunch when they think a lion is around. So, prolonged stress interferes with digestion, leading to ulcers, acid reflux, and IBS.
• Immune System: When we’re stressed, our immune system dials down—great if you’re trying to avoid inflammation during a crisis, but terrible if the crisis never ends. This makes us more vulnerable to infections and slower to recover.
• Reproduction and Hormones: Sapolsky explains that stress hormones mess with our sex hormones. This can lead to reduced fertility, lower libido, and irregular menstrual cycles.
• Brain Fog and Memory: Chronically high cortisol levels shrink areas of the brain responsible for memory and mood regulation, which is why we feel foggy and forgetful under prolonged stress.

Why Our Stress Response is Outdated

Prof. Sapolsky argues that our stress response evolved for immediate physical threats—not for modern, low-grade, endless stressors. When we’re stuck in traffic, waiting for a delayed flight, or dreading a meeting, our bodies respond as if we’re about to be attacked. But these “attacks” aren’t life-threatening; they just won’t go away, and we don’t get the zebra’s chance to relax and reset.

The “Personality Factor” and Managing Stress

Some people seem to breeze through life without sweating the small stuff. Prof. Sapolsky suggests that personality plays a role here. Pessimists, perfectionists, or those who ruminate tend to experience more stress. But there’s good news: practicing optimism, reframing situations, or engaging in stress-relieving activities (like meditation or spending time with friends) can help reset the stress response.

So, What Can We Do?

Prof. Sapolsky doesn’t leave us hanging in despair. He offers practical tips to “trick” our bodies into calmness. Physical exercise, social support, mindfulness, and humor are all effective ways to reset the body’s stress response. In other words, we may not be able to escape modern life’s stressors, but we can learn to handle them like a zebra—turning off the stress switch when it’s no longer needed.

In Prof. Sapolsky’s eyes, the moral of the story is clear: We’ve got to stop being the species that stresses itself sick. By learning to chill out, we’re not just improving our moods; we’re protecting our hearts, guts, brains, and more. So, let’s take a lesson from the zebra—don’t let life’s lions live rent-free in your head.

#health #stress #cortisol